The pilot reported that upon receiving clearance to taxi from air traffic control, he proceeded to taxi onto what he thought was the centerline of taxiway Charlie in nighttime conditions. During the taxi, the airplane suddenly turned to the right. The pilot stated he stopped the airplane and thought something on the ground made "the wheel turn" and he looked at the right wing, noting nothing abnormal. He added that after they were airborne, he saw that part of the right wingtip was separated. The pilot continued the flight and landed uneventfully at his destination.Postaccident examination of the airplane revealed that the right wing was structurally damaged. A portion of the accident airplanes right wingtip was located underneath a damaged wing on an unoccupied airplane that was parked adjacent to taxiway Charlie at the departure airport. The pilot reported that there were no mechanical failures or malfunctions with the airplane that would have precluded normal operation.